modules/indexing/src/main/java/org/apache/ignite/internal/processors/query/h2/H2ConnectionWrapper.java

/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.apache.ignite.internal.processors.query.h2;

import java.sql.Connection;
import java.sql.SQLException;
import org.apache.ignite.internal.processors.query.IgniteSQLException;
import org.apache.ignite.internal.util.typedef.F;
import org.apache.ignite.internal.util.typedef.internal.S;
import org.apache.ignite.internal.util.typedef.internal.U;
import org.jetbrains.annotations.Nullable;

/**
 * Wrapper to store connection with currently used schema and statement cache.
 */
public class H2ConnectionWrapper implements AutoCloseable {
    /** */
    private static final int STATEMENT_CACHE_SIZE = 256;

    /** */
    private final Connection conn;

    /** */
    private volatile String schema;

    /** */
    private volatile H2StatementCache statementCache;

    /**
     * @param conn Connection to use.
     */
    H2ConnectionWrapper(Connection conn) {
        this.conn = conn;

        initStatementCache();
    }

    /**
     * @return Schema name if schema is set, null otherwise.
     */
    public String schema() {
        return schema;
    }

    /**
     * @param schema Schema name set on this connection.
     */
    public void schema(@Nullable String schema) {
        this.schema = schema;
    }

    /**
     * Connection for schema.
     *
     * @param schema Schema name.
     * @return Connection.
     */
    public Connection connection(@Nullable String schema) {
        if (schema != null && !F.eq(this.schema, schema)) {
            try {
                conn.setSchema(schema);

                this.schema = schema;
            }
            catch (SQLException e) {
                throw new IgniteSQLException("Failed to set schema for DB connection for thread [schema=" +
                    schema + "]", e);
            }
        }

        return conn;
    }

    /**
     * @return Connection.
     */
    public Connection connection() {
        return conn;
    }

    /**
     * @return Statement cache corresponding to connection.
     */
    public H2StatementCache statementCache() {
        return statementCache;
    }

    /**
     * Clears statement cache.
     */
    public void clearStatementCache() {
        initStatementCache();
    }

    /**
     * @return Statement cache size.
     */
    public int statementCacheSize() {
        return statementCache == null ? 0 : statementCache.size();
    }

    /**
     * Initializes statement cache.
     */
    private void initStatementCache() {
        statementCache = new H2StatementCache(STATEMENT_CACHE_SIZE);
    }

    /** {@inheritDoc} */
    @Override public String toString() {
        return S.toString(H2ConnectionWrapper.class, this);
    }

    /** Closes wrapped connection. */
    @Override public void close() {
        U.closeQuiet(conn);
    }
}